http://modeles7.meteociel.fr/modeles/gens/graphe_ens3.php?x=225&ext=1&y=245&run=18&runpara=0 

Number 7 for me please 

http://modeles7.meteociel.fr/modeles/gens/runs/2016122618/gens-7-1-192.png 

This is also a beauty

http://old.wetterzentrale.de/pics/MT8_London_ens.png 

a lot more uncertainty regarding the cold spell. May not even happen at all. This could well do down as yet another defeat snatched from the jaws of victory. A common theme in the modern era. The northern jet is simply too strong to enable blocking where we need it

I fear for what the morning will herald for cold weather fans

You are so funny

Comedy gold

For gawd's sake, don't you start with this modern era nonsense, Beast!

Don't be such a melt, like a snowman.

There are more important things.

I said this time yesterday there was a signature for 2 topplers in the GEFS.  Today there is a firm signature for one toppler (the first).

The Meto has backed off it's stellar charts.

The search for prolonged and deep cold continues! (will the ECM throw a curve ball... though?)

2 Things -

1. Always remember Murphy's Law
2. When there is a chance of cold it is foolhardy to look beyond 144 hours.   Anyhow, here are the GEFS and the Met O 144:

STOP PRESS - BUT, as hinted at in my intro, the ECM does throw this into the mix at 144:by far the best for cold as we head into FI, which is clearly at round 120, so anything beyond is JFF as someone once said.

The ECM sends the cold shot to Germany and the eastern Alps.  More runs needed.

Rather the missing data the main issue IMO is that posters looking for an extended cold spells are looking well out into FI so outlook is bound to change from run to run. Happens all the time regardless of whether Xmas. Only the initial incursion is anywhere near the reliable timeframe .

Also look at the Met office 6 to 15 day forecast . It is broadly in line with the models and was written yesterday and seems a good reflection of cirrent thinking.  Northerly incursion. High pressure. Possibility of further incursion. We should be looking for the 2nd incursion now but this time period is well out in FI.

Ian Ferguson on "missing" Christmas data

Meteorological trade runs 24-7 even over Christmas(!); the satellite data keeps churning; many aircraft providing data... etc. I've never heard such a 'theory' espoused anywhere before.

Ian Ferguson on UKMO 144hrs

Incidentally, someone posted along lines of UKMO-GM being of no credence at T+144, but I've never seen evidence for that published or cited elsewhere.

An extended cold spell was never modelled, there was no garden path, just hints at a cool down.  the 'suggestion' as far as I can see is two shots of cold 5 or so days apart the first one now looking likely but severity very much open for debate.

I really don't get the comments in here this morning, we're just seeing variations on a theme. 

I'm guessing it's just me that sees the repeated N Atlantic - Greenland ridging as a rather good thing. There are some wind up merchants here which gives a totally warped view to the casual reader.

Perhaps some would also do well to heed IF's points. The prospects of cold and snowy conditions continue to be higher in the current outlook that at any other stage of the winter so far. If you're looking for Jan 1963 or Dec 2010 however, I would urge a little caution!

Edit: Basically what the post above mine says   (Thanks b2b).

I'm not sure whether most of them are wind up merchants or just don't understand basic probability. I hope it's the former because if not it suggests that schooling in the UK is dire! I also notice the comments about the UM 144 are back in circulation but give it a short time and these will be juxtaposed with equally daft suggestions that the Met Office have secret model data which blows away the "free" stuff we view and analyse.  The big picture hasn't changed significantly this morning with a cold snap this weekend looking the form horse and a more varied and at times colder pattern likely to continue as we head into January.

The charts look great to me this morning!

Maybe I'm missing something.

The ECM in particular is stunning. 

The general theme really remains unaltered and one shouldn't let individual OP runs distract from the mean trend.

Ignoring the 'questionable' charts of the 25-26th December we are pretty much where we were on Christmas Eve.

A cold front sweeps south on News Years Day bringing the risk of snow showers to exposed coasts in the north. Given a NE'ly feed on the 2nd we are looking at a wintry shower risk extending to eastern Britain, even the SE could see some wintry showers over the higher ground for a time before the High Pressure topples on the 3rd/4th.

A spell of cold and frosty weather is then likely for a time whilst the high pressure makes up its mind where it goes next. There has been enough evidence to suggest it may retrogress for a second bite but confidence is low again as the jam tomorrow scenarios are once again in FI.

lol.

I think people are feeling disheartened because (on GFS) , we are seeing repeated Atlantic ridging/amplification rather than sustained Greenland High. Both options are plausible at this time, and both options have snow opportunities associated with them, albeit one more than the other. More runs needed on that front. GEFS show the uncertainty - quite a significant spread. http://old.wetterzentrale.de/pics/MT2_Manchester_ens.png

http://old.wetterzentrale.de/pics/MT8_Manchester_ens.png - some very cold runs in there, but quite a significant split between very cold and much milder. The op one of the milder options. 

Meanwhile, IF has had quite the ramp on the other side! 

Anyone who claims they can predict what the weather will be doing in 10 days from this needs to fill in my lottery slip...

http://old.wetterzentrale.de/pics/MT8_London_ens.png

The Geneva ensemble shows even more uncertainty.

http://old.wetterzentrale.de/pics/MT8_Genf_ens.png

An initial northerly looks very likely. After that all options are on the table.

As for the often repeated claim that the jet has somehow got stronger in the "modern era", that appears to be completely backwards. The Arctic has got warmer in recent years, which has led to a weaker jet stream, in fact the correlation between the weakening strength of the jet stream and the reduction in Arctic ice is shown nicely here:

https://www.skepticalscience.com/jetstream-guide.html#climate

Deleted this post as there seem to be some issues with it.

Martin

Not too much to add to some of the more sensible comments from me

Initial Northerly looking good - don't expect snow to be prominent away from parts of Scotland and the coastal fringes and if anything else does crop up it's a bonus. Other than that enjoy the crisp sunny airmass

Longevity of cold snap still TBA but initial cold shot not looking too long, thereafter trend remains for HP to re-establish in the mid Atlantic with further cold shot to follow after a milder interlude.

It'll be interesting given then -pna talk to see if we do get any easterly influence. There are a few easterlies showing up in FI although in this kind of pattern it'd be unusual if there wasn't.

GFS ens look good to me - plenty of cold shown, with some tasty looking members in there. Still some going milder of course so not universally cold, but better than they were a week or two back